From: Rafael Zalamena <rzalamena@opensourcerouting.org>
Date: Thu, 31 Jan 2019 20:36:44 +0000 (-0200)
Subject: bfdd: slow down on peer connection loss
X-Git-Tag: 7.1_pulled~230^2~9
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=b912b189c72cc5225be1b43ced5f2af3b1d86dcb;p=mirror%2Ffrr.git

bfdd: slow down on peer connection loss

Lets be more RFC 5880 compliant and slow down control packets on
connection loss.

Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
---

diff --git a/bfdd/bfd.c b/bfdd/bfd.c
index 53d8601e9c..ea3a586f95 100644
--- a/bfdd/bfd.c
+++ b/bfdd/bfd.c
@@ -191,6 +191,9 @@ void ptm_bfd_ses_dn(struct bfd_session *bfd, uint8_t diag)
 
 	ptm_bfd_snd(bfd, 0);
 
+	/* Slow down the control packets, the connection is down. */
+	bs_set_slow_timers(bfd);
+
 	/* only signal clients when going from up->down state */
 	if (old_state == PTM_BFD_UP)
 		control_notify(bfd);
@@ -369,18 +372,8 @@ static struct bfd_session *bfd_session_new(int sd)
 	bs->detect_mult = BFD_DEFDETECTMULT;
 	bs->mh_ttl = BFD_DEF_MHOP_TTL;
 
-	/*
-	 * BFD connection startup must use slow timer.
-	 *
-	 * RFC 5880, Section 6.8.3.
-	 */
-	bs->cur_timers.desired_min_tx = BFD_DEF_SLOWTX;
-	bs->cur_timers.required_min_rx = BFD_DEF_SLOWTX;
-	bs->cur_timers.required_min_echo = 0;
-
-	/* Set the appropriated timeouts for slow connection. */
-	bs->detect_TO = (BFD_DEFDETECTMULT * BFD_DEF_SLOWTX);
-	bs->xmt_TO = BFD_DEF_SLOWTX;
+	/* Initiate connection with slow timers. */
+	bs_set_slow_timers(bs);
 
 	/* Initiate remote settings as well. */
 	bs->remote_timers = bs->cur_timers;
@@ -923,6 +916,22 @@ void bs_final_handler(struct bfd_session *bs)
 	control_notify_config(BCM_NOTIFY_CONFIG_UPDATE, bs);
 }
 
+void bs_set_slow_timers(struct bfd_session *bs)
+{
+	/*
+	 * BFD connection must use slow timers before going up or after
+	 * losing connectivity to avoid wasting bandwidth.
+	 *
+	 * RFC 5880, Section 6.8.3.
+	 */
+	bs->cur_timers.desired_min_tx = BFD_DEF_SLOWTX;
+	bs->cur_timers.required_min_rx = BFD_DEF_SLOWTX;
+	bs->cur_timers.required_min_echo = 0;
+
+	/* Set the appropriated timeouts for slow connection. */
+	bs->detect_TO = (BFD_DEFDETECTMULT * BFD_DEF_SLOWTX);
+	bs->xmt_TO = BFD_DEF_SLOWTX;
+}
 
 /*
  * Helper functions.
diff --git a/bfdd/bfd.h b/bfdd/bfd.h
index e6fb25da0d..2cd2b87a1f 100644
--- a/bfdd/bfd.h
+++ b/bfdd/bfd.h
@@ -527,6 +527,7 @@ void bfd_set_polling(struct bfd_session *bs);
 void bs_state_handler(struct bfd_session *, int);
 void bs_echo_timer_handler(struct bfd_session *);
 void bs_final_handler(struct bfd_session *);
+void bs_set_slow_timers(struct bfd_session *bs);
 const char *satostr(struct sockaddr_any *sa);
 const char *diag2str(uint8_t diag);
 int strtosa(const char *addr, struct sockaddr_any *sa);